Catalyst for preparation of pentafluoroethane and preparation method thereof

Abstract

The method of preparing a chromium oxide catalyst for preparation of pentafluoroethane using a chloroethane compound includes heat treating chromium hydroxide powder at a temperature not higher than 300° C. to obtain chromium oxide powder, heat treating metal hydroxide, at a temperature not higher than 300° C. to obtain metal oxide powder, mixing 85˜99.5 wt % of the chromium oxide powder with 0.5˜15 wt % of the metal oxide powder to obtain a mixture, forming the mixture into a pellet, calcining the pellet at 200-300° C. using nitrogen gas, and fluorinating the pellet at 300-320° C. using a gas mixture including N 2 and HF, and then at 320-380° C. using HF gas. The fluorination catalyst prepared using the method of this invention can be effectively used to prepare pentafluoroethane at a high yield using a chloroethane compound.

1. A method of preparing a chromium oxide catalyst for preparation of pentafluoroethane from a chloroethane compound, said method comprising the steps of:
 heat treating a chromium hydroxide powder at a temperature not higher than 300° C. to obtain chromium oxide powder; 
 heat treating a metal hydroxide at a temperature not higher than 300° C. to obtain metal oxide powder, said metal hydroxide being selected from a group consisting of magnesium hydroxide, iron hydroxide, molybdenum hydroxide, vanadium hydroxide and aluminum hydroxide; 
 mixing 85% to 99.5% by weight of said chromium oxide powder with 0.5% to 15% by weight of the metal oxide powder so as to obtain a mixture; 
 forming said mixture into a pellet; 
 burning said pellet at 200° C. to 300° C. with nitrogen gas; and 
 fluorinating the burned pellet at 300° C. to 320° C. with a gas mixture containing N 2  and HF and then at 320° C. to 380° C. with HF gas. 
 
     
     
       2. The method of  claim 1 , the chloroethane compound being perchloroethane or 1,1-dichloro-2,2,2-trifluoroethane. 
     
     
       3. The method of  claim 1 , wherein the step of heat treating a metal hydroxide comprises heat treating the metal hydroxide at a temperature of 300° C. for a time period of 2 hours, said heat treating being carried out under atmospheric conditions. 
     
     
       4. The method of  claim 1 , wherein the step of fluorinating the burned pellet comprises fluorinating the burned pellet with HF gas at a temperature of 380° C. for a time period of no more than 3 hours.